大约有 41,000 项符合查询结果(耗时:0.0504秒) [XML]

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How to subtract 30 days from the current datetime in mysql?

... SELECT * FROM table WHERE exec_datetime BETWEEN DATE_SUB(NOW(), INTERVAL 30 DAY) AND NOW(); http://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html#function_date-add ...
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Return rows in random order [duplicate]

... SELECT * FROM table ORDER BY NEWID() share | improve this answer | follow | ...
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Write a number with two decimal places SQL server

... try this SELECT CONVERT(DECIMAL(10,2),YOURCOLUMN) share | improve this answer | follow | ...
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What is the most efficient/elegant way to parse a flat table into a tree?

...port recursive queries in standard syntax. WITH RECURSIVE MyTree AS ( SELECT * FROM MyTable WHERE ParentId IS NULL UNION ALL SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentId = t.Id ) SELECT * FROM MyTree; I tested recursive queries in MySQL 8.0 in my presentation Recursive ...
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How to count occurrences of a column value efficiently in SQL?

... This should work: SELECT age, count(age) FROM Students GROUP by age If you need the id as well you could include the above as a sub query like so: SELECT S.id, S.age, C.cnt FROM Students S INNER JOIN (SELECT age, count(age) a...
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How can I add an item to a SelectList in ASP.net MVC

Basically I am looking to insert an item at the beginning of a SelectList with the default value of 0 and the Text Value of " -- Select One --" ...
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INSERT INTO … SELECT FROM … ON DUPLICATE KEY UPDATE

...olumns named in the INSERT INTO clause, and the second part references the SELECT columns. INSERT INTO lee(exp_id, created_by, location, animal, starttime, endtime, entct, inact, inadur, inadist, smlct, smldur, smldist, larct, lardur, lardist, ...
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'IF' in 'SELECT' statement - choose output value based on column values

... SELECT id, IF(type = 'P', amount, amount * -1) as amount FROM report See http://dev.mysql.com/doc/refman/5.0/en/control-flow-functions.html. Additionally, you could handle when the condition is null. In the case of...
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How to return result of a SELECT inside a function in PostgreSQL?

... bigint , ratio bigint) AS $func$ BEGIN RETURN QUERY SELECT t.txt , count(*) AS cnt -- column alias only visible inside , (count(*) * 100) / _max_tokens -- I added brackets FROM ( SELECT t.txt FROM token t WHERE t.charty...
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Python set to list

..., 'symmetric_difference_update', 'union', 'update'] (removed __ because of char limit) – user825286 Jul 26 '11 at 10:48 ...